Method and apparatus for diagnosing faults in a hybrid internet protocol network

ABSTRACT

An Ethernet switch ( 112 ) has a communications interface ( 122 ), and a controller ( 124 ). The controller is programmed to receive ( 202 ) an IP query packet generated by a receiver for collecting telemetry data between a source and the receiver in a multicast network, translate ( 206 ) the IP query packet to an Ethernet query packet, collect ( 208 ) in the Ethernet query packet telemetry data from the Ethernet switch, and submit ( 218 ) the Ethernet query packet to the next network element of the multicast network. Additional embodiment are disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/191,758, filed Jul. 28, 2005, the disclosure of which is herebyincorporated by reference.

FIELD OF THE INVENTION

This invention relates generally to IP (Internet Protocol) diagnosticsystems, and more particularly to a method and apparatus for diagnosingfaults in a hybrid IP network.

BACKGROUND OF THE INVENTION

As hybrid packet networks continue to evolve, the need for diagnosingtroubled connections becomes increasingly important to the serviceprovider of such networks. Hybrid IP (Internet Protocol) networks caninclude, for example, conventional IP routers and Ethernet switches forinterconnecting parties. It is very common for these networks to supportmulticast communications (e.g., streaming video) between a source andmany receivers such as computer terminals. When a user of a receiverexperiences a communication interruption, it is common practice for theuser to call the service provider and seek technical assistance.

Typically, service providers employ conventional diagnostic toolsoperating at the receiver of the end user to diagnose faults in themulticast connection. Tools such as “Mtrace” can be used to trace themulticast route from the receiver to the source. Consequently, theservice provider can quickly diagnose, for example, a faulty router orlinks and thereby take evasive action to restore service to the enduser. In hybrid networks, however, Ethernet switches serve as apass-through devices in which IP mtrace packets are relayed betweenswitches without inclusion of telemetry data from the switches.Consequently, if the communication issue arises from a fault at anEthernet switch or sequence of switches, the service provider has nomeans of detecting the fault with a conventional Mtrace diagnostic test.

A need therefore arises for a method and apparatus for diagnosing faultsin a hybrid IP network.

SUMMARY OF THE INVENTION

Embodiments in accordance with the invention provide a method andapparatus for diagnosing faults in a hybrid IP network.

In a first embodiment of the present invention, an IP router and anEthernet switch, respectively, has a computer-readable storage mediumfor conducting diagnostics in a multicast network having networkelements comprising one or more IP (Internet Protocol) routers andEthernet switches. The storage medium of an Ethernet switch has computerinstructions for receiving an IP query packet generated by a receiverfor collecting telemetry data between a source and the receiver,translating an IP query packet to an Ethernet query packet, collectingin the Ethernet query packet telemetry data from the Ethernet switch,and submitting the Ethernet query packet to the next network element ofthe multicast network. The storage medium of an IP router has computerinstructions for receiving the Ethernet query packet, translating theEthernet query packet to an IP query packet, collecting in the IP querypacket telemetry data from the IP router, and submitting the IP querypacket to the next network element of the multicast network.

In a second embodiment of the present invention, an IP router and anEthernet switch, respectively, operate according to a method forconducting diagnostics in a multicast network having network elementscomprising one or more IP (Internet Protocol) routers and Ethernetswitches. At an Ethernet switch, the method comprises the steps ofreceiving an IP query packet generated by a receiver for collectingtelemetry data between a source and the receiver, translating an IPquery packet to an Ethernet query packet, collecting in the Ethernetquery packet telemetry data from the Ethernet switch, and submitting theEthernet query packet to the next network element of the multicastnetwork. At an IP router, the method comprises the steps of receivingthe Ethernet query packet, translating the Ethernet query packet to anIP query packet, collecting in the IP query packet telemetry data fromthe IP router, and submitting the IP query packet to the next networkelement of the multicast network.

In a third embodiment of the present invention, an Ethernet switch has acommunications interface, and a controller. The controller is programmedto receive an IP query packet generated by a receiver for collectingtelemetry data between a source and the receiver in a multicast network,translate the IP query packet to an Ethernet query packet, collect inthe Ethernet query packet telemetry data from the Ethernet switch, andsubmit the Ethernet query packet to the next network element of themulticast network.

In a fourth embodiment of the present invention, an IP router has acommunications interface, and a controller. The controller is programmedto receive an Ethernet query packet generated by an Ethernet switch forcollecting telemetry data between a source and a receiver in a multicastnetwork, translate the Ethernet query packet to an IP query packet,collect in the IP query packet telemetry data from the IP router, andsubmit the IP query packet to the next network element of the multicastnetwork.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is block diagram of a hybrid network of Ethernet switches and IProuters according to an embodiment of the present invention;

FIG. 2 is block diagram of the IP router and the Ethernet switch,respectively, according to an embodiment of the present invention;

FIG. 3 is block diagram depicting a format of an Ethernet query packetaccording to an embodiment of the present invention; and

FIGS. 4-5 depict flowcharts of methods operating in the Ethernetswitches and IP routers, respectively, according to an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims defining the features ofembodiments of the invention that are regarded as novel, it is believedthat the embodiments of the invention will be better understood from aconsideration of the following description in conjunction with thefigures, in which like reference numerals are carried forward.

FIG. 1 is block diagram of a hybrid network 100 of Ethernet switches 114and IP routers 112 according to an embodiment of the present invention.The present illustration represents a multicast network created betweena source 102 (e.g., a server supplying streaming video) and a receiver104 (e.g., a computer terminal of an end user). A multicast network inthe present context extends the broadcast concept of one to many byallowing the sending of one transmission to many users in a definedgroup, but not necessarily to all users in that group.

Large service providers typically encounter a mix of network elementssuch as shown in FIG. 1. The Ethernet switches 114 can, for example,represent IGMP (Internet Group Management Protocol) snooping Ethernetswitches. These switches can reside in a customers network, or can besupplied by the service provider. The IP routers 112 are conventionalInternet Protocol routers available from many vendors such as, forexample, Cisco™ Corporation.

FIG. 2 is basic block diagram of an IP router 112 and Ethernet switch114, respectively, according to an embodiment of the present invention.Each device includes a communications interface 122 and a controller124. In the case of an IP router 112, the communications interface 122includes conventional technology that serves to interconnect the IProuter 112 with other IP network elements of the hybrid network shown inFIG. 1. The interface 122 is bidirectional in that IP packets can eitherbe generated or received at the interface and redirect to other networkelements according to the routing tables established at the IP router112. The controller 124 utilizes conventional computing technology suchas one or more microprocessors, DSPs (Digital Signal Processors) andassociated media storage (e.g., RAM, SRAM, DRAM, Flash, or disk media)for controlling operations of the IP router 112 in accordance with thepresent invention.

Like the IP router 112, the Ethernet switch 114 can include acommunications interface 122 and a controller 124. These components,however, are tailored for Ethernet traffic as defined by such standardsas IEEE 802.3. The communications interface 122 in this instancesupports CSMA/CD (Carrier Sense Multiple Access Collision Detection)access method to handle simultaneous demands. This interface is one ofthe most widely implemented LAN standards. A newer version of Ethernet,called 100 Base-T (or Fast Ethernet) supports data transfer rates of 100Mbps. The present invention, however, can be applied to any Ethernetswitch 114 technology including 1G and 10G. The controller 124 in thisembodiment can utilize conventional processing technology similar towhat was described for the IP router 112 to support the functions of theEthernet switch 114 in accordance with the present invention.

It should be noted that the communications interface 122 of the IProuters 112 and Ethernet switches 114, respectively, also utilizeconventional technology for hybrid interconnects between said systemsthereby allowing the formation of the hybrid network shown in FIG. 1.

FIGS. 4-5 depict flowcharts of methods 200 and 300 operating in theEthernet switches and IP routers, respectively, according to anembodiment of the present invention. Method 200 represents the flow of adiagnostic packet in a trace route 110 initiated by the receiver 104 ofFIG. 1 under the control of, for example, a management system (notshown) of the service provider of the hybrid network connected to thereceiver 104 by way of another communication link 105 of the serviceprovider's network.

The trace route 110 traces each network element connecting the receiver104 and the source 102 in a multicast network. Once the trace packetreaches the source 102, a unicast IP response packet returns back on aresponse route 111. The response route 111 can travel on the samenetwork elements as did the trace route 110 or in a unicast pathdifferent from these elements. In either case, the IP response packettravels in the reverse direction towards the receiver 104. The IPresponse packet includes telemetry information collected from eachnetwork element connecting the source 102 and receiver 104. The receiver104 can process or relay this telemetry information to the serviceprovider who in turn determines where and why a communicationinterruption may have occurred.

Referring back to FIG. 4, method 200 begins with step 202 where theEthernet switch 114 receives a diagnostic packet. The diagnostic packetcan be an IP query packet (such as an mtrace packet) or an Ethernetquery packet. In the illustration of FIG. 1, the first network elementcoupled to the receiver 104 is an Ethernet switch 114. In thisillustration the Ethernet switch 114 receives an IP query packet fromthe receiver 104. It will be appreciated that the multicast network ofFIG. 1 configuration is simply illustrative. That is, the receiver 104could have in the alternative been coupled to an IP router 112, and theEthernet switches 114 could have been located upstream in the multicastnetwork. Thus, whether an IP query packet comes directly from thereceiver 104 or and IP router 112, the Ethernet switch 114 is programmedto process either format.

In the present instance, however, it is assumed that the packet receivedand detected in steps 202 and 204 is an IP query packet, in which casethe Ethernet switch 114 proceeds to step 206 where it translates the IPquery packet to an Ethernet query packet. FIG. 3 is block diagramdepicting a format of an Ethernet query packet according to anembodiment of the present invention. In this embodiment, the Ethernetquery packet can include one or more of the following telemetry fields:

-   -   An arrival time of the Ethernet query packet at the switch 114;    -   An upstream network element address, which identifies the next        network element (i.e., an IP router 112 or Ethernet switch 114)        located adjacent to the switch in question, and upstream towards        the source 102 of the multicast data;    -   A downstream network element address, which identifies the        previous network element (i.e., an IP router 112 or Ethernet        switch 114) located adjacent to the switch in question, and        downstream towards the receiver 104;    -   A multicast channel number (or group number), which identifies        the channel used between the source 102 and receiver 104 in the        multicast network;    -   An input packet count at the arrival time, which identifies the        number of packets received by the switch at the time the query        packet arrives;    -   An output packet count at the arrival time, which identifies the        number of packets transmitted by the switch at the time the        query packet arrives;    -   A total packet count at the arrival time, which identifies the        total number of packets processed by the switch at the time the        query packet arrives;    -   A protocol operating at the receiving Ethernet switch (e.g.,        IGMP);    -   A packet hop limit, which sets a limit on how many network        elements can be traversed by the query packet; and    -   A diagnostic code, which provides a state of operation of the        Ethernet switch 114.

The diagnostic code can in turn can include:

-   -   A no error code corresponding to a no-fault state in the        receiving Ethernet switch 114;    -   A wrong interface code corresponding to an IP or Ethernet query        packet received by the Ethernet switch from a network element        not belonging to the multicast network;    -   A channel route error code corresponding to an IP or Ethernet        query packet received from a network element on a multicast        network channel different from that used by the receiver; and    -   A router error code corresponding to receiving an IP query        packet from an unexpected IP router.

The foregoing fields are illustrative of the telemetry fields anddiagnostic codes that can be used in an Ethernet query packet forisolating and diagnosing faults in a hybrid network of IP routers 112and Ethernet switches 114. It would be obvious to an artisan with skillin the art that other telemetry data not mentioned above that can proveuseful for isolating faults in a hybrid network such as shown in FIG. 1is within the scope and spirit of the claimed invention.

Referring back to FIG. 4, the Ethernet switch 114 populates theaforementioned telemetry fields in step 208. In step 210, the switch 114decrements the packet hop limit This field is initially established bythe receiver 104 with a number that represents the number of allowablenetwork element hops. This field can prove useful in limiting the numberof hops a query packet undertakes in a multicast network. It isespecially important in that it can be used to destroy query packetsthat get lost in the network for any apparent reason. As each Ethernetswitch 114 receives an Ethernet query packet, this field is decrementedin step 210. If it reaches zero, for instance, the Ethernet switch 114can assume that the packet is lost, because the limit is set such thatthe number should never reach zero in a diagnostic session. Since querypackets can consume significant processing resources of a switch, it isimportant that a means be available to destroy lost query packets asperformed by steps 212 and 214.

If the hop limit is not exceeded, however, the Ethernet switch 114proceeds to step 216 where it checks if it is coupled to the source 102.If not, the Ethernet switch 114 proceeds to step 218 where it submitsthe Ethernet query packet to the next network element. If the networkelement happens to be an Ethernet switch 114, such switch will processthe query packet according to steps 208 through 222, thereby appendingadditional telemetry data such as described in FIG. 3. If, on the otherhand, the Ethernet switch 114 is coupled to the source 102, then themulticast diagnostic trace has been completed, in which case the switchproceeds to step 220 where it translate the Ethernet query packet to anIP response packet and submits it in step 222 back to the receiver 102through the response route 111 described earlier.

FIG. 5 depicts method 300 operating in the IP routers 112. In step 302,a diagnostic packet is received. If the packet is detected in step 304as an Ethernet query packet, then the router 112 proceeds to step 306where it translates the Ethernet query packet to a conventional IP querypacket. In step 306, the IP query packet collects the telemetry data ofthe router much like in the case of a conventional Mtrace packet. If, onthe other hand, the diagnostic packet received in step 302 is detectedin step 304 as an IP query packet, then step 306 is bypassed andtelemetry collection takes place in step 308. If the router 112 iscoupled to the source 102, it translates the IP query packet to an IPresponse packet in step 314 and transmits said packet back to thereceiver 104 on the response trace 111. Otherwise, the router 112proceeds to step 312 where it submits the IP query packet to the nextnetwork element.

Methods 200 and 300 describe algorithms operating in the Ethernetswitches 114 and IP routers 112 which allow any hybrid configuration ofthese network elements for conducting an end-to-end diagnostic trace.This invention therefore provides a means for further visibility intothe operations of a multicast network not presently available in priorart systems.

It should be evident by now that the present invention can be realizedin hardware, software, or a combination of hardware and software.Moreover, the present invention can be realized in a centralizedfashion, or in a distributed fashion where different elements are spreadacross several interconnected processors. Thus, any kind of computingdevice or other apparatus adapted for carrying out methods 200 and 300described above is suitable for the present invention.

It should be also evident that the present invention may be used formany applications. Thus, although the description is made for particulararrangements and methods, the intent and concept of the invention issuitable and applicable to other arrangements and applications notdescribed herein. It would be clear therefore to those skilled in theart that modifications to the disclosed embodiments described hereincould be effected without departing from the spirit and scope of theinvention.

In accordance with various embodiments of the present invention, themethods described herein are intended for operation as software programsrunning on a computer processor. Dedicated hardware implementationsincluding, but not limited to, application specific integrated circuits,programmable logic arrays and other hardware devices can likewise beconstructed to implement the methods described herein. Furthermore,alternative software implementations including, but not limited to,distributed processing or component/object distributed processing,parallel processing, or virtual machine processing can also beconstructed to implement the methods described herein.

A software program in the present context means any expression, in anylanguage, code or notation, of a set of instructions intended to cause asystem having an information processing capability to perform aparticular function either directly or after either or both of thefollowing: a) conversion to another language, code or notation; b)reproduction in a different material form.

It should also be noted that the software implementations of the presentinvention as described herein are optionally stored on a tangiblestorage medium, such as: a magnetic medium such as a disk or tape; amagneto-optical or optical medium such as a disk; or a solid statemedium such as a memory card or other package that houses one or moreread-only (non-volatile) memories, random access memories, otherre-writable (volatile) memories or Signals containing instructions. Adigital file attachment to e-mail or other self-contained informationarchive or set of archives sent through signals is considered adistribution medium equivalent to a tangible storage medium.Accordingly, the invention is considered to include a tangible storagemedium or distribution medium, as listed herein and includingart-recognized equivalents and successor media, in which the softwareimplementations herein are stored.

Although the present specification describes components and functionsimplemented in the embodiments with reference to particular standardsand protocols, the invention is not limited to such standards andprotocols. Each of the standards for Internet and other packet switchednetwork transmission (e.g., TCP/IP, UDP/IP, HTML, HTTP) representexamples of the state of the art that are applicable to the presentinvention. Such standards are periodically superseded by faster or moreefficient equivalents having essentially the same functions.Accordingly, replacement standards and protocols having the samefunctions are considered equivalents.

The described embodiments ought to be construed to be merelyillustrative of some of the more prominent features and applications ofthe invention. It should also be understood that the claims are intendedto cover the structures described herein as performing the recitedfunction and not only structural equivalents. Therefore, equivalentstructures that read on the description should also be construed to beinclusive of the scope of the invention as defined in the followingclaims. Thus, reference should be made to the following claims, ratherthan to the foregoing specification, as indicating the scope of theinvention.

1. First and second portions of a computer-readable storage medium eachhaving computer instructions for operating an Ethernet switch and aninternet protocol router, respectively, for conducting diagnostics in amulticast network having network elements comprising one or moreinternet protocol routers and Ethernet switches, the first portion ofthe computer-readable storage medium operating in the Ethernet switch,comprising computer instructions that, when executed by at least onefirst processor of the Ethernet switch, cause the at least one firstprocessor to perform operations comprising: receiving an internetprotocol query packet generated by a receiver for collecting telemetrydata between a source and the receiver; translating the internetprotocol query packet to an Ethernet query packet; collecting in theEthernet query packet telemetry data from the Ethernet switch, whereinat least one telemetry field of the Ethernet switch includes an arrivaltime of the Ethernet query packet at the Ethernet Switch; and submittingthe Ethernet query packet to the next network element of the multicastnetwork; the second portion of the computer-readable storage mediumoperating in the internet protocol router, comprising computerinstructions that, when executed by at least one second processor of theinternet protocol router, cause the at least one second processor toperform operations comprising: receiving the Ethernet query packet;translating the Ethernet query packet to the internet protocol querypacket; and submitting the internet protocol query packet to the nextnetwork element of the multicast network.
 2. The first and secondportions of computer-readable storage medium of claim 1, wherein thefirst portion of the computer-readable storage medium of the Ethernetswitch comprises computer instructions which when executed by the atleast one first processor cause the at least one first processor toperform operations comprising: collecting in the Ethernet query packettelemetry data from the Ethernet switch, wherein another telemetry fieldof the Ethernet switch includes a diagnostic code providing a state ofoperation of the Ethernet switch.
 3. The first and second portions ofcomputer-readable storage medium of claim 1, wherein the second portionof the storage medium of the internet protocol router comprises computerinstructions which when executed by the at least one second processorcause the at least one second processor to perform operationscomprising: collecting in the internet protocol query packet telemetrydata from the internet protocol router.
 4. The first and second portionsof computer-readable storage medium of claim 1, wherein the secondportion of the storage medium of the internet protocol router comprisescomputer instructions which when executed by the at least one secondprocessor cause the at least one second processor to perform operationscomprising: collecting in the internet protocol query packet telemetrydata from the internet protocol router; translating the internetprotocol query packet into an internet protocol response packet; andsubmitting the IP response packet to the receiver.
 5. The first andsecond portions of computer-readable storage medium of claim 1, whereinthe first portion of the storage medium of the Ethernet switch comprisescomputer instructions which when executed by the Ethernet switch causethe Ethernet switch to perform operations comprising: collecting in theEthernet query packet telemetry data from a root internet protocolrouter; translating the Ethernet query packet into an internet protocolresponse packet; and submitting the IP response packet to the receiver.6. The first and second portions of computer-readable storage medium ofclaim 1, wherein the Ethernet switch comprises an internet groupmanagement protocol snooping Ethernet switch.
 7. The first and secondportions of computer-readable storage medium of claim 1, wherein thefirst portion of the computer-readable storage medium of the Ethernetswitch comprises computer instructions which when executed by the atleast one first processor cause the at least one first processor toperform operations comprising collecting the telemetry data in theEthernet query packet from at least one of a group of telemetry itemscomprising an upstream network element address, a downstream networkelement address, a multicast channel number, an input packet count atthe arrival time, an output packet count at the arrival time, a totalpacket count at the arrival time, a protocol operating at the Ethernetswitch, or a diagnostic code.
 8. The first and second portions ofcomputer-readable storage medium of claim 7, wherein the first portionof the computer-readable storage medium of the Ethernet switch comprisescomputer instructions which when executed by the at least one firstprocessor cause the at least one first processor to perform operationscomprising generating the diagnostic code from at least one of a groupof diagnostic codes comprising a no error code corresponding to ano-fault state in the Ethernet switch, a wrong interface codecorresponding to the internet protocol packet or the Ethernet querypacket received by the Ethernet switch from a network element notbelonging to the multicast network, a channel route error codecorresponding to the internet protocol packet or the Ethernet querypacket received from a second network element on a multicast networkchannel different from that used by the receiver, or a router error codecorresponding to receiving an expected internet protocol query packetfrom internet protocol router.
 9. The first and second portions ofcomputer-readable storage medium of claim 1, wherein the receiverinitializes a packet hop limit in the internet protocol query packet,and wherein the first portion of the computer-readable the storagemedium of the Ethernet switch comprises computer instructions which whenexecuted by the at least one first processor cause the at least onefirst processor to perform operations comprising: decrementing thepacket hop limit; and upon exceeding the packet hop limit, discardingthe Ethernet query packet.
 10. A method, comprising: receiving, by anEthernet switch, an internet protocol query packet generated by areceiver for collecting telemetry data between a source and thereceiver; translating, by the Ethernet switch, the internet protocolquery packet to an Ethernet query packet; collecting by the Ethernetswitch, in the Ethernet query packet telemetry data from the Ethernetswitch, wherein at least one telemetry field of the Ethernet Switchincludes an arrival time of the Ethernet query packet at the EthernetSwitch; and submitting, by the Ethernet switch, the Ethernet querypacket to the next network element of the multicast network; receiving,by an internet protocol router, the Ethernet query packet; translating,by the internet protocol router, the Ethernet query packet to theinternet protocol query packet; and submitting, by the internet protocolrouter, the internet protocol query packet to the next network elementof the multicast network.
 11. The method of claim 10, comprising:collecting, by the Ethernet switch, in the Ethernet query packettelemetry data from the Ethernet switch.
 12. The method of claim 10,comprising: collecting, by the internet protocol router, in the internetprotocol query packet telemetry data from the internet protocol router.13. The method of claim 10, comprising: collecting, by the internetprotocol router, in the internet protocol query packet telemetry datafrom the internet protocol router; translating, by the internet protocolrouter, the internet protocol query packet into an internet protocolresponse packet; and submitting, by the internet protocol router, theinternet protocol response packet to the receiver.
 14. The method ofclaim 10, comprising: collecting, by the Ethernet switch, in theEthernet query packet telemetry data from a root internet protocolrouter; translating, by the Ethernet switch, the Ethernet query packetinto an internet protocol response packet; and submitting, by theEthernet switch, the internet protocol response packet to the receiver.15. The method of claim 10, wherein the Ethernet switch comprises aninternet group management protocol snooping Ethernet switch.
 16. Themethod of claim 10, wherein the telemetry data collected in the Ethernetquery packet comprises at least one of a group comprising an upstreamnetwork element address, a downstream network element address, amulticast channel number, an input packet count at the arrival time, anoutput packet count at the arrival time, a total packet count at thearrival time, a protocol operating at the Ethernet switch, or adiagnostic code.
 17. The method of claim 16, wherein the diagnostic codecomprises at least one of a group of diagnostic codes comprising a noerror code corresponding to a no-fault state in the Ethernet switch, awrong interface code corresponding to the internet protocol packet orthe Ethernet query packet received by the Ethernet switch from a networkelement not belonging to the multicast network, a channel route errorcode corresponding to the internet protocol packet or the Ethernet querypacket received from a network element on a multicast network channeldifferent from that used by the receiver, or router error codecorresponding to receiving an expected internet protocol query packetfrom internet protocol router.
 18. The method of claim 10, wherein thereceiver initializes a packet hop limit in the internet protocol querypacket, and wherein the method comprises: decrementing, by the Ethernetswitch, the packet hop limit; and upon exceeding the packet hop limit,discarding, by the Ethernet switch, the Ethernet query packet.
 19. AnEthernet switch, comprising: a communications interface; a memorystoring computer instructions; a controller coupled to the memory,wherein the controller, responsive to executing the computerinstructions, performs operations comprising: receiving an internetprotocol query packet generated by a receiver for collecting telemetrydata between a source and the receiver in a multicast network;translating the internet protocol query packet to an Ethernet querypacket; collecting in the Ethernet query packet telemetry data from theEthernet switch, wherein at least one telemetry field of the EthernetSwitch includes an arrival time of the Ethernet query packet at theEthernet switch; and submitting, the Ethernet query packet to the nextnetwork element of the multicast network.
 20. An internet protocolrouter, comprising: a communications interface; a memory storingcomputer instructions: a controller coupled to the memory, wherein thecontroller, responsive to executing the computer instructions performsoperations comprising: receiving an Ethernet query packet generated byan Ethernet switch having at least one field for telemetry forcollecting telemetry data between a source and a receiver in a multicastnetwork, wherein the at least one field includes at least an arrivaltime of the Ethernet query packet at the Ethernet switch; translatingthe Ethernet query packet to an internet protocol query packet; andsubmitting the internet protocol query packet to the next networkelement of the multicast network.